Rear view mirrors, both center-mounted inside a vehicle passenger compartment and side-mounted outside the passenger compartment, are used to enable a driver of the vehicle to observe objects that are behind the vehicle, while the driver's gaze remains directed generally forward. Such mirrors are ubiquitous means for providing data--actual visual images of objects that are behind the vehicles--to drivers.
In addition, a significant amount of data is presented to a driver of a vehicle in analog form, e.g., by gages, and in digital form. Digital data can be presented by means of speedometer read-outs, radio read-outs, temperature read-outs, and so on.
As recognized by the present invention, it can be advantageous to combine data sources not only to realize manufacturing cost savings, but also to promote safety and data presentation effectiveness. More specifically, in the rear view mirror context, the present invention recognizes that most drivers readily accept and use mirrors to know what objects are behind their vehicles and thereby improve driving safety, and the present invention further recognizes that the use of mirrors can be promoted even further by presenting additional data on the mirrors to stimulate relatively more frequent use of the mirrors. Moreover, by presenting data on a mirror that otherwise would be presented elsewhere in the vehicle at a perhaps less convenient location, the effectiveness of the presentation of the data is improved. In other words, the present invention recognizes that it is possible that data presented on a mirror is more accessible than data presented in other vehicle locations that would not otherwise attract the driver's attention as much as does a rear view mirror.
As still further recognized herein, however, it is desirable that the data essentially be superimposed on the reflective surface of the mirror, instead of requiring that a portion of the reflective surface be blocked by the data presentation. This is to enhance the cooperation between the two displays (i.e., an alpha-numeric digital display and the image display of the reflective surface) and to avoid relinquishing areas of the reflective surface and, thus, avoid reducing the field of view that a conventional mirror could otherwise provide.
Accordingly, it is an object of the present invention to provide a rear view system which presents to a driver an image of the area behind a vehicle. Another object of the present invention is to provide a rear view system which presents alpha-numeric data superimposed on a mirrored surface, with the data representing a vehicle variable such as time, speed, temperature, etc. Still another object of the present invention is to provide a rear view system which presents alpha-numeric data on a mirrored surface that is incorporated into the mirror. Yet another object of the present invention is to provide a rear view system that is easy to use and cost-effective to manufacture.